This invention relates to document storage and more particularly to provision of a shelf component for a mixed media library unit.
Modern day libraries may contain an assortment of documents. In its broadest sense a document is a medium on which an assemblage of data is recorded by writing or printing or by other processes such as those of a photographic or electronic nature. Thus, a document may be sheetlike and consist, for example, of one or more individual looseleaf pages, an accordian-folded computer printout or a prebound article such as a book or periodical. Documents also may take other forms. Thus, a document may be a reel of film or, as in computer facilities, it may consist of magnetic tape or disc.
Storage of documents in mixed media libraries is typically accomplished by means of suspension filing systems and regular shelving. Suspension filing systems have found wide use in the filing of large format items such as computer printouts, flow diagrams, program listings and the like, and a wide variety of storage files have been devised to accommodate different materials to suspension filing. A common kind of suspension filing system is the so-called center hook system, which in its simplest form comprises a single horizontal support bar to which appropriate files provided with hooks and designed to accommodate the documents to be filed may be detachably secured. One kind of storage file for center hook suspension is a modified post binder for stationery materials which incorporates in its spine a centered or eccentrically mounted hook, as disclosed in U.S. Pat. Nos. 3,865,445, 3,580,360 and 4,056,296. Reels of computer tape also may be fitted with circular storage bands adapted for center hook suspension filing, in the manner illustrated in U.S. Pat. No. 3,696,935. Those documents not easily accommodated to suspension storage with prior art files are commonly stored on regular shelving, as, for example, books, periodicals, discs and cassettes. Unfortunately in mixed media libraries employing both suspension filing systems and regular shelving, there is often a resultant loss in user convenience since related documents in different form may have to be stored remotely from one another or at least in different areas of the library. This problem has been alleviated to some extent by provision of so-called mixed media library units of the type comprising a library stand or frame to which are affixed or releasably secured components in the form of flat shelves for storing books, cassettes, and the like and horizontal support bars for accommodating reels of tape fitted with storage bands of the type described above or files with centered or eccentrically mounted hooks. These shelves and support bars are generally attached to the library stand in cantilever fashion one above the other with the spacing between such components often being adjustable. While the flat shelf components are adequate for storing items such as magazines and books, either flat or upright between book ends, they are not suitable for holding such items so that their front covers are suitably displayed to the viewer in the manner achieved with certain forms of magazine display racks.